Modern life is damaging our ears more than we realize

In an article in The Conversation, Rebecca S. Dewey, a research Fellow in Neuroimaging, addresses noise exposure, calling it “the main cause of preventable hearing loss worldwide.” She cites a recently published study in The Lancet that finds “that living in a noisy city increases your risk of hearing damage by 64%.” Why do cities increase the risk so dramatically? Dewey points to obvious sources–work noise at a construction site or recreational noise at a nightclub–but adds that people “might be exposed to loud noises so constantly throughout the day that you don’t even realise they are there.” She also notes that many of us engage in “self-harm”–that is, exposing ourselves via mp3 players and mobile phones to damaging noise levels “with little more than a disclaimer from the manufacturers.”

Why is noise exposure a concern? Researchers now understand much more about how hearing loss develops and about the phenomenon of “hidden hearing loss.” Until recently it was believed that “noise-induced hearing loss resulted from damage to the sound-sensing cells in the cochlea,” says Dewey, but recent studies have shown that “even relatively moderate amounts of noise exposure can cause damage to the auditory nerve – the nerve connecting the inner ear to the brain.”

The standard audiology exam “measures hearing by finding the quietest sound a person can hear in a quiet environment,” but does not measure hidden hearing loss which affects “the ability to hear subtle changes in loud sounds,” what is called “supra-threshold.” Supra-threshold hearing is used to “understand conversations in a noisy room or hear someone talk over the sound of a blaring television.” In short, a traditional hearing test can’t detect hidden hearing loss. Attempts to measure it by playing a recording of speech masked with background noise “depends a lot on the ability of the patient to understand and cooperate with the test.”

Fortunately, progress is being made. Dewey is part of a team at the University of Nottingham working on using MRI scans to “detect hidden hearing loss by scanning the parts of the hearing system that connect the ears to the brain.” The goal is to “understand who is most at risk and act early to prevent further hearing loss.”

And prevention is key, because there currently is no treatment or cure for hidden hearing loss. So do yourself a favor and avoid loud noise when you can. Use earplugs when you cannot. Lower the volume on your personal audio devices. One day hearing loss may be treatable, but no one knows if that day is five years, ten years, or 20+ years away. Why gamble on a future cure when prevention works today?